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"Cable tray"Grounding bulkhead Bit by bit, I am trying to make my station more lightning resistant, with the ultimate goal of being able to stay on the air even during a thunderstorm, at least listening. I will update this article as I add more lightning protection. The first steps towards a lightning resistant station are having everything in the station at the same potential at all times, and providing a good path to ground.

Sunday morning I woke up to this sight. An entire tree top, about 20-25ft long, had come down and blocked both garage doors. I borrowed a saw from the neighbors across the street (thank you) and ended up spending most of Sunday sawing this treetop into pieces and dragging those pieces off the driveway. Luckily the damage to the roof was absolutely minimal.

Lately I've been gotten a lot of comment spam on my blog, which Mollom was unable to stop. As a result, I've turned off comments by anonymous users for now. Once I get back from the KVM forum, I'll look into installing one of the Drupal modules that allow people to authenticate with accounts from places like Facebook, so more people can post comments on my blog without needing an account.

Once I have that all set up, I can also think about migrating kernel newbies over to something like Drupal, so the wiki and forum can be integrated into one site.

While my wife was cooking dinner, the stove made a funny *pop* sound. After we stopped cooking, we noticed that the "element on" light is not coming off. Spent some quality time searching the net and examining the insides of the stove to figure out exactly which of the switches had trouble. New parts have been ordered, and the stove should be working as advertised again within a week or so...

A few monitor stands and two filing cabinets later, the home office is completely the way I want it to be. Left of the three monitors you can see the keyboard of my test system, the antenna switch, the LDG AT-200 Pro antenna tuner, and the Icom R75, which is my main radio for broadcast and ute listening. Above the left monitor is a maybe 50 year old painting by one Frits Bos, about whom I have found absolutely no information online. To the right of the monitors you can see the old Kenwood TS-930S, which is my main radio for amateur radio contacts. As you can see, the monitors are now at a more ergonomic height, and well above sleeping cat level.

Buster, our cat, loves sleeping next to my keyboard. He often sleeps in a ball, blocking part of my left monitor. I should buy taller monitor stands, so Buster can sleep next to my keyboard without blocking my view of the monitor. However, he is sleeping on top of my wallet, which he uses as a pillow...

After much planning and modeling of various different antenna types, I finally settled on a very simple antenna for 160. The reason? This one works just about as well as the larger more complicated antennas, yet it leaves enough room in my yard that I can build better antennas for the other bands, too.

The antenna I chose? The Double-L Antenna by K2KQ, a compact vertical dipole for 160m. I built a monoband version, though others have built this antenna for multiple bands.

Earlier this week I updated the Split LRU VM design document a little. Seemed like a good idea to tell people about it, since that page is not seen that often and I do get questions about Split LRU on a regular basis :)

The N6LF vertical H antenna is an off center fed, capacitively loaded, vertical short dipole. This antenna is a compact alternative to the quarter wave vertical, giving just a little bit less gain than a quarter wave vertical but without the extensive radial system a vertical requires to get decent gain. The gain pattern of the vertical H, shown on the right, is similar to that of a quarter wave vertical antenna, with only about 0.5dB gain difference between the peaks and the "nulls" at a 30 degree takeoff angle.

Common wisdom holds that the longer the radiating element on a capacity loaded short dipole is, the stronger the radiated signal. On the other hand, the closer the bottom capacity hat is to the ground, the higher the ground losses. This suggests that there may be some kind of sweet spot, where reduced ground losses are significant and reduced gain from a shorter radiator are no big deal yet. Lets find the sweet spot for a 160m vertical H antenna.